April is going to be unseasonably cold across most of Canada

Canadians in southeastern parts of the country can expect wintry weather until mid-April and cooler than average temperatures for the rest of the month.

Arctic air from the northwest and lake effect precipitation will combine to bring snow and a blast of cold to southern Ontario and Quebec late on Thursday and overnight into Friday.

This weather system comes on the heels of a storm that dropped significant snow, ice pellets and rain on parts of Ontario, Quebec and New Brunswick on Tuesday and early Wednesday.

“Much of Southern Canada is not looking too great here,” said Brett Anderson, a senior meteorologist at Accuweather. “It’s going to be either cold and dry, or it’s going to be raining or snowing for a big part of this week.”

Anderson said the cold air, and possibly snow, will persist over the weekend in Southern Canada but should begin to lift early next week.

“I think we’ll start seeing more of a trend back toward normal conditions, starting around the 10th of April, across much of Southern Canada,” Anderson said. “I don’t see any spring heatwaves anywhere through the next few weeks.”

Bob Smerbeck, another senior meteorologist at Accuweather said meteorologists saw this cold weather coming as far back as February. That’s when the polar vortex — a large pocket of cold air that hovers above the arctic that has begun to weaken — was disturbed and split in two.

“Typically your vortex is over the pole and you have this strong westerly ring of wind around that vortex and all the cold air stays bottled around the pole,” Smerbeck said.

But after the polar vortex split in February, the larger, stronger portion drifted over to Northern Europe and Asia, and the smaller portion, too weak to contain itself in the Arctic, leaked down into North America, bringing cold air with it.

“It’s even been very cold in Western Canada with these arctic air masses sliding down through parts of Alberta,” Smerbeck said. “And then they go through the southern Prairies and right across the Great Lakes toward Toronto.”

Some Canadians have escaped this spring’s unseasonably cold temperatures though. Smerbeck said Newfoundland and Labrador and Nova Scotia have enjoyed at least seasonal temperatures.

“It’s when you get to the Southern Prairies and take a stripe from there and extend it down across the lakes into Southern Ontario, that’s kind of where the cold has been more persistent,” he said.

“But once you get into the second half of April, I think the pattern’s going to relax some.”